Consolidated Statements Of Capitalization (Parenthetical) - $ / shares	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Common stock, par value	$ 0.50	$ 0.50
Revolving Credit Agreement, Due 2023 [Member]
Maturity date	2023	2023
Amortizing notes at 3.00% due 2022 [Member]
Interest rate	3.00%	3.00%
Maturity date	2022	2022
Notes at 2.40% due 2031 [Member]
Interest rate	2.40%	2.40%
Maturity date	2031	2031
Notes at 2.704% due 2030 [Member]
Interest rate	2.704%	2.704%
Maturity date	2030	2030
Notes at 3.01% due 2029 [Member]
Interest rate	3.01%	3.01%
Maturity date	2029	2029
Notes at 3.59% due 2050 [Member]
Interest rate	3.59%	3.59%
Maturity date	2050	2050
Notes at 4.28%, due 2049 [Member]
Interest rate	4.28%	4.28%
Maturity date	2049	2049
Notes at 5.64% due 2022 [Member]
Interest rate	5.64%	5.64%
Maturity date	2022	2022
Notes at 5.95% due 2034 [Member]
Interest rate	5.95%	5.95%
Maturity date	2034	2034
Minimum [Member] \| Long-Term Debt Of Subsidiaries 0.00% To 0.99% [Member]
Interest rate	0.00%	0.00%
Maturity date	2023	2023
Minimum [Member] \| Long-Term Debt Of Subsidiaries 1.00% To 1.99% [Member]
Interest rate	1.00%	1.00%
Maturity date	2023	2023
Minimum [Member] \| Long-Term Debt Of Subsidiaries 2.00% To 2.99% [Member]
Interest rate	2.00%	2.00%
Maturity date	2022	2022
Minimum [Member] \| Long-Term Debt Of Subsidiaries 3.00% To 3.99% [Member]
Interest rate	3.00%	3.00%
Maturity date	2022	2022
Minimum [Member] \| Long-Term Debt Of Subsidiaries 4.00% To 4.99% [Member]
Interest rate	4.00%	4.00%
Maturity date	2023	2023
Minimum [Member] \| Long-Term Debt Of Subsidiaries 5.00% To 5.99% [Member]
Interest rate	5.00%	5.00%
Maturity date	2023	2023
Minimum [Member] \| Long-Term Debt Of Subsidiaries 6.00% To 6.99% [Member]
Interest rate	6.00%	6.00%
Maturity date	2022	2022
Minimum [Member] \| Long-Term Debt Of Subsidiaries 7.00% To 7.99% [Member]
Interest rate	7.00%	7.00%
Maturity date	2022	2022
Minimum [Member] \| Long-Term Debt Of Subsidiaries 8.00% To 8.99% [Member]
Interest rate	8.00%	8.00%
Maturity date	2025	2025
Minimum [Member] \| Long-Term Debt Of Subsidiaries 9.00% To 9.99% [Member]
Interest rate	9.00%	9.00%
Maturity date	2026	2026
Maximum [Member] \| Long-Term Debt Of Subsidiaries 0.00% To 0.99% [Member]
Interest rate	0.99%	0.99%
Maturity date	2033	2033
Maximum [Member] \| Long-Term Debt Of Subsidiaries 1.00% To 1.99% [Member]
Interest rate	1.99%	1.99%
Maturity date	2039	2039
Maximum [Member] \| Long-Term Debt Of Subsidiaries 2.00% To 2.99% [Member]
Interest rate	2.99%	2.99%
Maturity date	2058	2058
Maximum [Member] \| Long-Term Debt Of Subsidiaries 3.00% To 3.99% [Member]
Interest rate	3.99%	3.99%
Maturity date	2056	2056
Maximum [Member] \| Long-Term Debt Of Subsidiaries 4.00% To 4.99% [Member]
Interest rate	4.99%	4.99%
Maturity date	2059	2059
Maximum [Member] \| Long-Term Debt Of Subsidiaries 5.00% To 5.99% [Member]
Interest rate	5.99%	5.99%
Maturity date	2043	2043
Maximum [Member] \| Long-Term Debt Of Subsidiaries 6.00% To 6.99% [Member]
Interest rate	6.99%	6.99%
Maturity date	2036	2036
Maximum [Member] \| Long-Term Debt Of Subsidiaries 7.00% To 7.99% [Member]
Interest rate	7.99%	7.99%
Maturity date	2027	2027
Maximum [Member] \| Long-Term Debt Of Subsidiaries 8.00% To 8.99% [Member]
Interest rate	8.99%	8.99%
Maturity date	2025	2025
Maximum [Member] \| Long-Term Debt Of Subsidiaries 9.00% To 9.99% [Member]
Interest rate	9.99%	9.99%
Maturity date	2026	2026